Method for decomposing rhodamine B wastewater

Abstract

The invention discloses a method for decomposing rhodamine B wastewater. The method comprises steps as follows: firstly, rhodamine B wastewater is desilted through a grating and then heated to 10-60 DEG C, the pH is regulated to 2-7, filtration is performed after 1 h, a filtrate obtained after the filtration is an electrolyte, one of platinum sheet, iron, copper, gold, ruthenium, palladium, aluminum, graphite, lead and BDD (boron-doped diamond) electrodes is taken as an oxidation electrode, a saturated calomel electrode is taken as a reference electrode, oxidation is performed for 5 min underthe condition of oxidation voltage of 1.0-1.5 V, rhodamine B wastewater is subjected to an electropolymerization reaction, and precipitates are produced; an electrolyte obtained after an oxidation reaction is filtered by a 0.22 mu m filter membrane, and a clear liquid is obtained. Compared with other methods for decomposing rhodamine B, the method has the advantages that C-N bonds on ethyl of rhodamine B are broken to generate -NH2, electropolymerization is performed on the electrode, polyaniline-like products are produced, the degradation time can be greatly shortened and electrolysis energyconsumption can be greatly reduced.

Description

technical field

[0001] The invention belongs to the field of environmental protection, in particular to a method for degrading rhodamine B wastewater. Background technique

[0002] Rhodamine B is a synthetic basic dye with bright pink color. Molecular formula is C 23 h 31 ClN 2 o 3 , with a molecular weight of 479.029. Rhodamine B can dissolve 0.78% in water and 1.47% in ethanol, and its maximum absorption wavelength is 554nm. Rhodamine B is used for printing and dyeing glossy paper, typing paper, waxy paper in paper industry, textile printing and dyeing industry and dyeing of feather products, straw, leather, etc. Rhodamine B has strong fluorescence in solution and was once used as a food additive , but later experiments proved that rhodamine B can cause cancer, and now it is not allowed to be used as food dye. The compound has good stability, large molecular weight, high chromaticity of wastewater, poor biodegradability, and bioaccumulation in terrestrial and aquati...

Examples

Embodiment 1

[0022] (1) Rhodamine B (C=100mg·dm -3 ) waste water grate sedimentation;

[0023] (2) Heating the rhodamine B wastewater treated in step (1) to 35°C, adjusting the pH to 4, and filtering after 1 hour; Fe in the wastewater 2+ , Fe 3+ , Ca 2+ Wait to form precipitate, and be filtered off, and the filtrate obtained by filtering is processed in the next step;

[0024] (3) take the filtrate after step (2) processing as electrolyte, adopt platinum electrode as oxidation electrode, adopt saturated calomel electrode as reference electrode, oxidation 5 minutes under the condition that oxidation voltage is 1.3V, rhodamine B waste water Electropolymerization occurs, resulting in a precipitate. Filter the oxidized electrolyte membrane to obtain a clear solution;

[0025] Obtain clear liquid after degrading by this embodiment, and the detection COD is 15mg·dm -3 .

Embodiment 2

[0027] (1) Rhodamine B (C=100mg·dm -3 ) waste water grate sedimentation;

[0028] (2) Heating the Rhodamine B wastewater treated in step (1) to 35°C, adjusting the pH to 2, and filtering after 1 hour; Fe in the wastewater 2+ , Fe 3+ , Ca 2+ Wait to form precipitate, and be filtered off, and the filtrate obtained by filtering is processed in the next step;

[0029] (3) take the filtrate after the treatment of step (2) as electrolyte, adopt BDD electrode as oxidation electrode, adopt saturated calomel electrode as reference electrode, oxidize 5 minutes under the condition that oxidation voltage is 1.1V, rhodamine B wastewater Electropolymerization occurs, resulting in a precipitate. Filter the oxidized electrolyte membrane to obtain a clear liquid;

[0030] Obtain clear liquid after degrading by this example, and the detection COD is 50mg·dm -3 .

Embodiment 3

[0032] (1) Rhodamine B (C=100mg·dm -3 ) water grid for sedimentation;

[0033] (2) Heating the rhodamine B wastewater treated in step (1) to 50°C, adjusting the pH to 3, and filtering after 1 hour; Fe in the wastewater 2+ , Fe 3+ , Ca 2+ Wait to form precipitate, and be filtered off, and the filtrate obtained by filtering is processed in the next step;

[0034] (3) take the filtrate after the treatment of step (2) as electrolyte, adopt gold electrode as oxidation electrode, adopt saturated calomel electrode as reference electrode, oxidize 5 minutes under the condition that oxidation voltage is 1.2V, rhodamine B waste water Electropolymerization occurs, and the oxidized electrolyte membrane is filtered to obtain a clear solution;

[0035] Obtain clear liquid after degrading by this example, and the detection COD is 45mg·dm -3 .

technical field

[0001] The invention belongs to the field of environmental protection, in particular to a method for degrading rhodamine B wastewater. Background technique

[0002] Rhodamine B is a synthetic basic dye with bright pink color. Molecular formula is C 23 h 31 ClN 2 o 3 , with a molecular weight of 479.029. Rhodamine B can dissolve 0.78% in water and 1.47% in ethanol, and its maximum absorption wavelength is 554nm. Rhodamine B is used for printing and dyeing glossy paper, typing paper, waxy paper in paper industry, textile printing and dyeing industry and dyeing of feather products, straw, leather, etc. Rhodamine B has strong fluorescence in solution and was once used as a food additive , but later experiments proved that rhodamine B can cause cancer, and now it is not allowed to be used as food dye. The compound has good stability, large molecular weight, high chromaticity of wastewater, poor biodegradability, and bioaccumulation in terrestrial and aquati...

Examples

Embodiment 1

[0022] (1) Rhodamine B (C=100mg·dm -3 ) waste water grate sedimentation;

[0023] (2) Heating the rhodamine B wastewater treated in step (1) to 35°C, adjusting the pH to 4, and filtering after 1 hour; Fe in the wastewater 2+ , Fe 3+ , Ca 2+ Wait to form precipitate, and be filtered off, and the filtrate obtained by filtering is processed in the next step;

[0024] (3) take the filtrate after step (2) processing as electrolyte, adopt platinum electrode as oxidation electrode, adopt saturated calomel electrode as reference electrode, oxidation 5 minutes under the condition that oxidation voltage is 1.3V, rhodamine B waste water Electropolymerization occurs, resulting in a precipitate. Filter the oxidized electrolyte membrane to obtain a clear solution;

[0025] Obtain clear liquid after degrading by this embodiment, and the detection COD is 15mg·dm -3 .

Embodiment 2

[0027] (1) Rhodamine B (C=100mg·dm -3 ) waste water grate sedimentation;

[0028] (2) Heating the Rhodamine B wastewater treated in step (1) to 35°C, adjusting the pH to 2, and filtering after 1 hour; Fe in the wastewater 2+ , Fe 3+ , Ca 2+ Wait to form precipitate, and be filtered off, and the filtrate obtained by filtering is processed in the next step;

[0029] (3) take the filtrate after the treatment of step (2) as electrolyte, adopt BDD electrode as oxidation electrode, adopt saturated calomel electrode as reference electrode, oxidize 5 minutes under the condition that oxidation voltage is 1.1V, rhodamine B wastewater Electropolymerization occurs, resulting in a precipitate. Filter the oxidized electrolyte membrane to obtain a clear liquid;

[0030] Obtain clear liquid after degrading by this example, and the detection COD is 50mg·dm -3 .

Embodiment 3

[0032] (1) Rhodamine B (C=100mg·dm -3 ) water grid for sedimentation;

[0033] (2) Heating the rhodamine B wastewater treated in step (1) to 50°C, adjusting the pH to 3, and filtering after 1 hour; Fe in the wastewater 2+ , Fe 3+ , Ca 2+ Wait to form precipitate, and be filtered off, and the filtrate obtained by filtering is processed in the next step;

[0034] (3) take the filtrate after the treatment of step (2) as electrolyte, adopt gold electrode as oxidation electrode, adopt saturated calomel electrode as reference electrode, oxidize 5 minutes under the condition that oxidation voltage is 1.2V, rhodamine B waste water Electropolymerization occurs, and the oxidized electrolyte membrane is filtered to obtain a clear solution;

[0035] Obtain clear liquid after degrading by this example, and the detection COD is 45mg·dm -3 .

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